This clip demonstrates a normal colonoscopy and starts in the terminal ileum where the delicate villous architecture is well seen. The colonoscope is withdrawn into cecum. Here at the base of the cecum is the orifice of the appendix. In the tissue surrounding the appendiceal orifice, a speckled pattern of lymphoid aggregates can often be seen. During the colonoscopy, the endoscopist both insufflates the lumen of the colon with air and aspirates the small amount of liquid that remains from the preparation previously taken by the patient to cleanse the colon. The liquid often has a slightly yellowish tinge of bile. Backing out of the cecum, a better view of the ileocecal valve is obtained. It has a rounded slightly yellowish appearance. Traveling down the colon, a repeating pattern of pouches and folds are seen. These pouches are called haustra and the folds are referred to as the plicae semilunares or simply the semilunar folds. A word about the colonic tissue itself. The white dots seen throughout the exam are reflections of the colonoscope’s light off the tissues and back into the viewing lens. Normally the tissue has this glistening pink hue. Also visible is the delicate vascular plexus of capillaries that nurture the colonic mucosa. Here in the sigmoid colon, the earliest signs of diverticulosis are visible. These are outpouchings of the mucosa through the muscular layers of the colon and are seen commonly starting in the fifth decade of life. More dramatic examples can be found in other clips on the DAVE Project. At the of the exam, in the rectal vault, the colonoscope is retroflexed to provide a complete view of the anal verge where small tumors and internal hemorrhoids may be found.

Kelsey, PB (Nov 01 2005). Colon – Normal Colon. The DAVE Project. Retrieved Jun, 21, 2009, from http://daveproject.org/viewfilms.cfm?film_id=300